Races marked "hostile" have a chance to not give you anything in trade, with a message of "<race> hate you for no reason" in the log instead; this still costs the resources you sent them.
Friendly races, on the other hand, have a chance to produce a "<race> thinks your kittens are adorable" message, meaning they give you 25% more resources than they otherwise would have.
The odds of these events happening are based on your standing with the various races. The best way to improve this, is through purchasing Tradeposts, and having the Caravanserai upgrade; this improves your chance of a successful trade with a hostile race, or a boosted trade with friendly races by a small amount for each Tradepost.
The actual math involved is as follows:
Each non-neutral race has a "standing" number. The values are as follows:
- Friendly Races
- Lizards: 0.25
- Spiders: 0.15
- Hostile Races
- Griffins: 0.85
- Zebras: 0.7
Each Caravanserai-boosted Tradepost then increases hostile races' standing by .0035, and friendly races' standing by half as much.
For hostile races, the result is the chance of a successful trade. For friendly races, it is the chance for a boosted trade.
Also, the boost given for a friendly race thinking your kittens are adorable will only affect how much you get of the base resources listed; spice or blueprints gained won't get the 25% boost. Hostile races, however, will absolutely fail to give any spice, blueprints, or in the case of Zebras, titanium, if they hate you for no reason.
Craft effectiveness does not affect the upgrades in the Workshop menu, no. If you look further down on that tab, you should see a number of resources that you can craft out of other resources. Also, as a convenience, any crafted resource you have made previously will be listed on the left panel, under your main resources, with buttons for easy crafting. Each time you craft one of these resources, you will by default produce one unit of that resource. The workshop's craft effectiveness boost is to that amount produced.
So, with only one Workshop, spending 175 units of Wood will create 1.06 units of Beam. With five workshops, it will produce 1.3 units of Beam.
This boost is incredibly useful, especially as the game progresses, and you start crafting new resources out of other crafted resources. As well, it is one of the few things in the game that has no diminishing returns; a hundred Workshops means producing seven units of everything you craft.
One caveat: While crafting Wood out of Catnip does appear in the list on the left, Catnip Refinement is not affected by the Workshop craft effectiveness boost.
Best Answer
Per Brilliand's answer in this question, Mints give a certain amount of furs and ivory per tick in exchange for a cost in gold and catpower.
The reason it doesn't just say "x.xx furs per second" or something like that is because the amount of furs and ivory gained is based on your maximum catpower, rather than being a particular amount. Thus, you get a certain amount of "mintEffect" which then translates through your maximum catpower and becomes ivory and furs. The linked question includes the exact amounts (and the points that mints become a more effective use of catpower than manual hunting, although you'll likely still be best served doing both).